Missing element detection in a stem making machine



Ap 1959 J. J. BARRETT ETAL 2,882,523

MISSING ELEMENT DETECTION A STEM MAKING MACHINE Filed June 1, 1953 5Sheets-Sheet 1 I NVENTORS MEEE? 7 an? .14 2.x. PflEPVGCI.

ATTORNE April 14, 1952 J. J. BARRETT ETAL MISSING ELEMENT DETECTION IN ASTEM MAKING MACHINE I Filed June 1,1953

5 Sheets-Sheet 2 iNVENTORS JTJT 3458577 and z. 2?. Pmepaac 6%" 9 ATTORNEApril 14, 1959 J. J. EARRETT ETAL MISSING ELEMENT DETECTION IN A STEMMAKING MACHINE Filed June 1, 1953 5 Sheets-Sheet 3 Z2 ATTORNEY April14,1959 J. J. BARRETT ETAL 2,882,523-

MISSING ELEMENT DETECTION IN A STEM MAKING MACHINE Filed June 1. 1953 5Sheets-Sheet 4 I v AT'IZORNEY 5 Sheets-Sheet 5 April 14, 1959 J. J.BARRETT ET AL MISSING ELEMENT DETECTION IN A STEM MAKING MACHINE FiledJune 1, 1953 s M R 6 m5 m NE D R 0 E 0 1 mg n 67A 7 1 v 1 {Wm 5 TE 1mufl w hun n a ..I N MW 1 IL I... .T. 1 k 5 n M :3 j in w. F 5 -5 L M WUnited States PatentU MISSING ELEMENT DETECTION IN A STEM MAKING MACHINEJohn J. Barrett, Kearny, and Ralph R. Parducci, Wood- Ridge, N.J.,assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., acorporation of Pennsylvania Application June 1, 1953, Serial No. 358,7522 Claims. (Cl. 340-259) This invention relates to automatic stem-makingmachines and, more particularly, to a mechanism for devtecting, beforeperforming further operations which would result in fabrication of animperfect product, missing leadin wires in the stem assembly.

Present-day high-speed automatic stem-making machines usually provide arotor which indexes from station-tostation and has a plurality ofstem-receiving and fabricating heads corresponding in spacingperipherally of the rotor to the several stations. Certain operationsare performed at the successive stations and those of interest to thepresent invention are at the beginning of the cycle where a flare isfirst introduced into a head and held by jaws thereat, and then atsuccessive stations lead-in wires are fed, one at each station, throughthe flare into a holder constituting a part of the head and locatedbeneath the flare. A subsequent operation seals the glass at the lowerend of the flare around the lead-in wires, and the present inventioncontemplates detection in an assembly of stem and lead-in wires whereinone or more of the wires may be missing before the sealing operation isperformed.

According to the present showing, the stem assembly has four lead-inwires when correctly fabricated, but the inventive concept is equallyapplicable to assemblies intended to each have more or less lead-inwires in completed condition. Reference herein to four lead-in wiresaccordingly is to be understood as explanatory only of the arbitrarilyselected embodiment and not in a restrictive sense.

In its broad aspect, the invention proposes individual feelers for eachof the predetermined number of leadin wires.

. Also of generic character, an objective is to close an electricutilization circuit to a supplemental instrumentality each time anyfeeler fails to contact a lead-in wire at the place Where said wireshould be.

..I More specifically, an object of the invention is to avoid scrapingcontact of the lead-in wires by the detecting means and to avoid use ofthe lead-in wires as electrical conductors in operation of saiddetecting means or in the utilization circuit thereof.

A further object of the invention is to apply light pressure only uponthe lead-in wires by the feelers and ,of short duration.

Another object of the invention is provision of mechanism affordingpositive retention of the feelers away from the lead-in wires except forthe momentary circuit closing interval and then under influence ofspring loading for the feelers exerting insignificant bending moment onany lead-in wires present.

Yet another object of the invention is to incorporate the invention inexisting stem-making machines and operable at a regular indexed stationpreviously established in the operation of such machines, therebyavoiding an additional indexed stop specifically for detecting purposes.

Other objects of the invention will appear to persons skilled in the artto which it appertains as the description proceeds, both by directrecitation thereof and by implication from the context.

Referring to the accompanying drawings in which like numerals ofreference indicate similar parts throughout the several views:

Figure 1 is a plan of our improved missing lead-wire detector, inassembled location with the rotor of: a stem-making machine, and shownin its retracted position;

Figure 2 is an elevation thereof looking in a direction from right toleft in Fig. 1;

Figure 3 is an elevation of said detector looking from the bottom towardthe top of the sheet containing Fig.1 and omitting the rotor;

Figure 4 is a plan, on increased scale, of the detector with the feelersadvanced to engagement with lead-in wires of a stem assembly;

Figure 5 is an elevation similar to Fig. 3 showing operation of thefeelers in connection with a stem having a missing lead-in wire;

Figure 6 is a plan, on increased scale, of Fig. 5;

Figure 7 is an elevation looking in a direction opposite from Fig. 2;and

Figure 8 is a diagrammatic representation of the utilization circuitinvolved with our invention. 5

In the specific embodiment of the invention illustrated in saiddrawings, and first considering its general relation to an existingstem-making machine, it is to be observed that it is general practice toprovide a rotor 10 (Figs. 1, 2, 4, 6 and 7) which indexes to a definitenumber and location of stations, designated sequentially herein byletters of the alphabet, A, B, C, D and E for the first several stationsof the cycle of operation. For each station on the rotor there isprovided a head 11 con structed and operated to receive and hold theconstitutent elements of the stern assembly during fabrication. Noattempt has been made to show the complete head construction as it iswell known in the art. Indicative of essential steps pertinent to thepresent invention station A may be considered the initial station of thecycle at which a glass flare 12 is introduced into said head and held'by jaws 13 above weld pockets 14 located in a holder 15 on the rotor,said pockets being equal in number and spacing to the intended numberand spacing of lead-in wires 16 in the stem assembly. At the foursuccessive stations, B, C, D and E, for the specific four-Wire assemblyarbitrarily selected for the present showing, the lead-in wires 16 arefed, one at a time, into the said pockets so that the fourth wire is fedat station E. All of said wires extend through the flare 12 and havetheir ends projecting therefrom. It is here called to attention thatthere is a space (Fig. 2) between the top of holder 15 and bottom offlare 12 thereby permitting hereinafter described feelers to enter thatspace and make contact with the wires 16 close to the weld pocket 14.

At the same station E at which the fourth or last wire is positioned, weprovide for detecting whether one or more may be missing by the deviceconstituting the subject matter of the present invention of which thef0ll0W'- ing. is a more detailed description.

Conveniently located in proximity to the rotor and station E is anupright fixed post 17 (Figs. l-3, 5 and 7) next to which is a verticallyreciprocating member 18 having a roller 19 thereon riding in and guidedby a longitudinal slot 20 in the post. The said member 18 is a part ofthe lead-in wire feeding mechanism shown in U.S. Patent No. 2,042,520,issued June 2, 1936 to I. Flaws, Jr. and accordingly is synchronizedwith the indexing of the machine. We make use of the post 17 as asupport for the subject invention and utilize said member 18 to furnishthe actuation therefor.

At an appropriate elevation on said post 17 we clamp a bracket 21 (Figs.1-3, 5 and 7) to maintain a fixed position, the end portion of thebracket away from the post being shownas protruding under the lowestlevel of the heads 11, well below the same; Bolted or otherwise fixed onsaid end portion of the bracket 21 is a stationary rail 22 (Figs. 1-7)extending horizontally outward approximately in a direction tangentialof the rotor 10 and in a plane parallel to the nearest pair of wires 16,or pockets 14 therefor, located at rest at station E. On said rail 22 isa slidable carriage 23 which is drawn normally inward toward the rotorby a spring 24 (Figs. 1, 2 and 7) attached to and extending from aforward end portion of the carriage to a fixed knob 25 next the bracketsupported end of the rail. Said carriage 23 is adapted to be retractedor moved to its outward position by a reciprocating cam 26 (Figs. 1-5and 7) attached to and depending from aforesaid member 18, said carriagehaving a laterally protruding roller 27 adjustably mounted on a plate27a provided with a slot 27b (Figs. 1 and 2) for non-frictional drivebetween said cam 26 and carriage 23. The adjustment for said rollerenables the carriage to be made to register at its inward position atthe correct position to bring the feelers 33 (Figs. 1-7) exactlyopposite the lead-in wires 16. When the cam 26 is in its uppermostposition, the carriage 23 is fully retracted as in Figures 1, 2 and 3,and when the cam is in its lowermost position, as in Figures 4, 5, 6 and7, the carriage is in its most advanced position toward the rotor 10,being actuated thereto by spring 24.

At the side of said carriage 23 away from the cam 26 and post 17 andconstituted as part of said carriage is a chassis 28 with an upright leg29 at the top of which is a lateral or upper horizontal shelf 30.Further down on the leg 29 but at an elevation above that of the rail22, and, like the upper shelf 30, on the opposite side of the leg fromthe post, is a lower horizontal shelf 31. The locations and indexing aresuch that when the head 11 at station E of Fig. l is at a position ofrest thereat, carriage 23 moves inward toward that head with the uppershelf 30 at a level below the flare 12 and flare gripping jaws 13 at alevel above said shelf such that the space between the holder 15 andflare is just above the said upper shelf.

Secured on the top of upper shelf 30 (Figs. 2, 3, 5 and 7) is ahorizontally grooved guide plate 32, the direction of the grooves beingperpendicular to the direction of sliding of the carriage 23. In saidgrooves are slidable feelers 33 held therein by an overlying top plate34. Said upper shelf 30, guide plate 32 and top plate '34 are shaped toprovide a cut-out or alcove 35 at the side toward the rotor head 11(Fig. 1) at station B such that when the carriage moves inward thecutout or alcove 35 admits the end of the holder 1.5 and lead-in wires16 to be received laterally therein and at that time the respectivelead-in wires in the space between the top of the holder and bottom ofthe flare 12 will be directly in the path of sliding of the feelers 33.Each feeler is here shown as having a wide and concave T-end (Figs. 4and 6) directed transversely of the cut-out 35 so as to assureengagement with the lead-in wire 16 protruding from the flare 12 eventhough the wire may not be standing prefectly upright, since the weldpockets 14 provide considerable clearance for receiving said wires. Atthe time when the carriage 23 moves to align the feelers 23 opposite tothe lead-in wires, said feelers are fully retracted with the T-endsthereof drawn back into engagement with the alcove walls which mayconveniently act as limiting stops for retraction of said feelers. Theopposite or stem ends of the feelers project from the opposite edges ofthe guide plate 32 and have rod-re- 7 ceiving holes 36 (Figs. 1 and 4)near the said ends.

Sliding of the feelers is under control of rods 37 (Figs.

l-7), one for each feeler, located in front of the shelves 30, 31 andwhich extend upwardly from the lower shelf 31 past the upper shelf 30'a'nd'thr'ough the respective holes 36 of the feelers. The lower ends ofthe rods 37 are each secured in a hub 38 (Figs. 4, 6 and 7) individualto each rod as a single spoke therefrom. Spiral springs 39 (Figs. 2, 3,5 and 7) extend between opposite rods tending to swing said rods towardeach other. Opposed to the inward pull of said springs 39 is a pair ofcrank pins 40 which cross in front of the rods 37 above the hubs 38 andsprings 39, said pins protruding laterally from crank arms 41 pivoted onthe same axles 42 as the hubs 38. Said crank arms 41 are integral partsof bell-crank levers 43 (Figs. l-6) providing coordinating arms 44directed toward each other and which overlap with an operative pivotalconnection 45. The arrangement is such that both crank arms 41 will becaused to swing simultaneously toward each other or simultaneously awayfrom each other the effect of which is to enable all of the feelers 33to move inward simultaneously under influence of spiral springs 39 or tobe retracted outwardly simultaneously by crank pins 40. A tension spring46 connected to depending lugs 47 on the bell crank levers maintainsresilient impetus tending to keep the crank pins 40 in engagement withrods 37 and tending to swing said rods outward with a force exceedingthe inward swinging force applied by the pair of spiral springs 39 onthe rods. However, the outwardly swinging force applied to the rods 37by the tension spring 46 is released at an appropriate moment in theoperative cycle by a positive operating means, at which time the spiralsprings 39 between the rods becomes effective.

The positive operating means for releasing the retractive force appliedby spring 46 comprises a laterally extending arm 48 (Figs. 1-3, and 5-6)on one hell crank lever 43 said arm having a link 49 pivoted thereto,said link extending down to, and having a slot 50 receiving (Figs. 1, 3and 4), a stud 51 which is held seated normally in the upper end of theslot by a spring 52 carried by the link. Said stud is fixed in andprojects at opposite sides of a rocker 53 which is pivoted at 54 to abracket 55 carried next to the bottom of leg 29. The outer end of saidstud carries a roller 56 the periphery of which projects toward the sideof carriage-operating cam 26 (Figs. 1, 3 and 4), and on that side is acam protuberance 57 properly located to engage said roller when the cam26 approaches its lowermost position and the carriage 23 is at itsinnermost position toward the rotor 10. As spring 52 holds rocker 53 atonly a slight upward inclination toward the roller-carrying end thereof,engagement of the protuberance 57 with the roller causes the rocker tofirst swing down, as viewed in Figs. 3, 5 and 7, by virtue of slot 50and spring 52, and then when protuberance 57 passes below the roller andstarts its up stroke, the rocker is swung outward momentarily, therebylifting the link 49 which thereupon swings the bell crank levers 43 in adirection moving crank pins 40 closer together. This movement inward ofcrank pins 40 removes retention of the rods 37 which then respond toimpetus of springs 33 to swing inwardly and slide the feelers 33 as farinward as they are permitted to go. Since the carriage 23 is at itsinward position, the feelers are directly opposed to the upwardlyprojecting lead-in wires 16 of the stem assembly and if all said wiresare present, as in Fig. 4, the feelers are stopped thereby and do notmove as far as they might if the Wires were not present. But if anylead-in wireis missing, the corresponding feeler may move furtherinward, as shown in Figs. 5 and 6,

and, of course, the actuating rod 37 for that particular feeler likewiseswings further inward.

Electrical contacts, here shown as pins 58 (Figs. 2-5 and 7-8), carriedby but insulated from chassis 28 are interposed in the path of swing ofsaid rods 37. Said contacts 58 are preferably eccentrically protrudingfrom a stud 59 enabling said pins 58 to be adjusted to only be engagedby the rods 37 which make the extra amplitude of swing resulting from alead-in wire 16 not being prese t, For normal operation, therefore, withall leadin wires present, the rods do not swing far enough to engagesaid contacts, but, as shown in Fig. 5, where a lead-in wire is missing,the corresponding rod continues its swing until stopped by engagementwith said contact. With the machine constituting ground for autilization electric circuit and a connection 60 (Figs. 2, 68) leadingto said circuit from said contact 58 and a supplemental instrumentality,such as buzzer 61, said instrumentality is electrically actuated. It isto be understood, however, that this buzzer is only indicative of anydesired instrumentality to be operated by closing of the electricalcircuit.

Since a buzzer and associated devices have been arbitrarily selected forillustrative purposes, as instrumentalities of the utilization circuit,a specific description thereof, as shown in Fig. 8, may accordingly begiven as follows: Line 62 is representative of above-mentioned groundconnection through the machine from rods 37 to one side of an inputsource 63, the other side of which connects through a micro switch 64and relay 65 to afore mentioned connection 60 to the contacts 58. Therelay, when caused to function by the closing of the circuit from a rod37 to a contact 58, closes two contacts of the relay 65, one a buzzercontact 66 which is in a cross line 67 to the grounded source, andanother contact 68, called an interlock contact, which shunts across, byline 69, between lines 60 and 62 and keeps current flowing through therelay even through the circuit through rods 37 and contacts 58 opens.The interlock contact 68 is held closed as long as the relay is excitedand the relay 65 continues to be excited as long as the interlockcontact is closed. And at the same time, the buzzer contact 66 is keptclosed by functioning of the relay. A cam 70 is provided in conjunctionwith the indexing mechanism, timed to open micro switch 64 for a longenough period to interrupt the current flow to the relay after thebuzzer or other instrumentality has served its purpose at the particularindexed position of the rotor, said micro switch being again closedready to pass current to the relay 65 when the next succeeding head 11(Fig. 1) comes to the same indexed position. It will be appreciated thatwhen the micro switch 64 opens the circuit, the relay is no longerexcited and both the interlock contact 68 and buzzer contact 66thereupon are opened. The arrangement accordingly obtains an extendedperiod of current flow to the buzzer 61 or other instrumentality, butrequires only a momentary closing of the circuit by rods 37 engagingcontacts 58. Consequently the feelers 33 are capable of functioningquickly and withdrawing to be out of the way and permit the carriage 23to withdraw promptly, thus enabling the detecting mechanism to beapplied at the same station at which the lead lead-in wire 16 isintroduced and therefore avoiding the provision of an extra station justfor detecting purposes. Furthermore the construction advantageouslyavoids utilization of the lead-in wires 16 as electrical conductors formissing wire detecting purposes.

While in accordance with the patent statutes one best known embodimentof the present invention has been illustrated and described in detail,it is to be particularly understood that the invention is not limitedthereto or thereby.

We claim:

1. A missing lead-in wire detector comprising a pair I of rods springloaded to tend to move toward each other, means normally holding saidrods swung away from each other, means for releasing said rod holdingmeans and for permitting momentary inward swing of said rods, feelershaving operative engagement with said rods whereby movement of the rodstoward each other obtains movement of said feelers toward each other,said feelers having a normal amplitude of movement for engagement withlead-in wires opposed thereto and having an excess amplitude of movementbeyond normal in event a lead-in wire is missing, and an electricalcontact in an electrical utilization circuit and forming a stopterminating the said excess amplitude of movement of the feelers, saidcircuit being closed by the termination of the excess amplitude ofmovement of said feeler passing the normal location of a lead-in wireand a signal instrumentality actuated by the closing of said circuit.

2. A missing lead-in Wire detector comprising a carriage slidablymounted for reciprocable movement in one direction, feelers slidablymounted in said carriage and reciprocable in a direction transverse todirection of reciprocable movement of the carriage, said feelers havinga normal amplitude of movement for engagement with lead-in wires opposedthereto and having an excess amplitude of movement beyond normal inevent a lead-in wire is missing, an electric circuit, stop means in suchelectric circuit for terminating the excess amplitude of movement ofsaid feelers and operable to close said circuit by engagement of afeeler with such stop means, a signal instrumentality activated by saidtermination and resultant closure of said circuit, a reciprocable barcam controlling reciprocation of both the said carriage and the saidfeelers, said cam having a direction of reciprocation transverse to bothof the aforesaid directions of reciprocation of the carriage andfeelers, means responsive to the reciprocation of said cam toreciprocate said carriage and means responsive to the reciprocation ofsaid cam to reciprocate said feelers.

References Cited in the file of this patent UNlTED STATES PATENTS1,547,393 Higgins July 28, 1925 1,682,464 Arelt et al. Aug. 28, 19282,329,599 Flaws Sept. 14, 1943 2,549,296 Dilts Apr. 17, 1951 2,700,154Dilts Jan. 18, 1955 FOREIGN PATENTS 674,459 Great Britain June 25, 1952

